Biology; Chemistry; Physics: Post your doubts here!

[asma tareen]

But is the other lette marked st the ventricle?

u mean the letter M???
its the pulmonary vein look the line points to the vessel

 

[Snowysangel]

u mean the letter M???
its the pulmonary vein look the line points to the vessel

Then shouldn't l be the right ventricle, since the pulmonary artery is energies from it?

 

[Snowysangel]

Then shouldn't l be the right ventricle, since the pulmonary artery is energies from it?

Or is that the superior vena cava?

 

[irfan.kheerdali]

explain how the effect of smoking on the alveoli could affect the general health of a smoker??

 

[TheStallion-Reborn]

explain how the effect of smoking on the alveoli could affect the general health of a smoker??

depends on the marks...if a lot of marks are available, then go for complete explanation of bronchitis and the causes and xplain emphysema.

 

[flaminheroes]

I have this doubt about biology. in excretion. like when the cappiliries take all the nutrients back from the convulated tubules in the kidney, why doesnt it take the waste products back too? i mean diffusion is suppose to happen because the concentration of the waste products is lower in the cappiliries but higher in the tubules.

 

[TheStallion-Reborn]

I have this doubt about biology. in excretion. like when the cappiliries take all the nutrients back from collecting duct in the kidney, why doesnt it take the waste products back too? i mean diffusion is suppose to happen because the concentration of the waste products is lower in the cappiliries but higher in the collecting duct.

tag me when u get the answer

 

[TheStallion-Reborn]

I have this doubt about biology. in excretion. like when the cappiliries take all the nutrients back from collecting duct in the kidney, why doesnt it take the waste products back too? i mean diffusion is suppose to happen because the concentration of the waste products is lower in the cappiliries but higher in the collecting duct.

i don't think u need to knw tht....im hearing the term 'collecting duct' for the very first time, nor have i ever seen any question based on knowledge regarding this....

 

[flaminheroes]

i don't think u need to knw tht....im hearing the term 'collecting duct' for the very first time, nor have i ever seen any question based on knowledge regarding this....

wait agh they take all the nutrients from the convulated tubules ._. woops. not the collecting duct

 

[Snowysangel]

I have this doubt about biology. in excretion. like when the cappiliries take all the nutrients back from the convulated tubules in the kidney, why doesnt it take the waste products back too? i mean diffusion is suppose to happen because the concentration of the waste products is lower in the cappiliries but higher in the tubules.

The brain sends a message to the renal tubule to select and reabsorb only certain chemicals from the glomerulus fluid as per the body needs

 

[Snowysangel]

explain how the effect of smoking on the alveoli could affect the general health of a smoker??

Smoke contains tar which is a carcinogenic and causes rapid growth of lung tissues. Carbon monoxide and other irritants destroy the cilia lining the inner walls of both the trachea and the bronchus/bronchioles, causing mucus to accumulate. Dust and bacteria get stuck to this mucus and induce a smokers cough. Coughing aggressively due to this causes the cross walls in the alveoli to rupture. This reduces the surface area to volume ratio of the alveoli making gaseous exchange more difficult. Thus the smoker can't breathe properly and suffers from shortness of breath

 

[Khadija_1234]

http://papers.xtremepapers.com/CIE/Cambridge International O Level/Biology (5090)/5090_w06_qp_2.pdf
Q4 part (c)

 

[Snowysangel]

http://papers.xtremepapers.com/CIE/Cambridge International O Level/Biology (5090)/5090_w06_qp_2.pdf
Q4 part (c)

The dry mass of the food storage region would remain the same while that of the plumule and radicle would increase gradually, as the glucose acquired from photosynthesis would directly be transported to the growing regions and there wouldn't be any need for it to be stored. Since the plant is already getting glucose from photosynthesis, it doesn't need to utilize it from the storage organ ie cotyledon so it's mass remains the same..:I think :S

 

[Snowysangel]

http://papers.xtremepapers.com/CIE/Cambridge International O Level/Biology (5090)/5090_w06_qp_2.pdf
Q4 part (c)

Could someone explain 8 or to me? :S

 

[flaminheroes]

The brain sends a message to the renal tubule to select and reabsorb only certain chemicals from the glomerulus fluid as per the body needs

b-but isnt diffusion like natural? arnt the waste products suppose to diffuse there naturally?

 

[Snowysangel]

b-but isnt diffusion like natural? arnt the waste products suppose to diffuse there naturally?

*active transport. The cells of the nephrons respire to produce the energy

 

[Asif1223]

Any tips for tomorrow's exam-Biology(5090)Paper 2

 

[asma tareen]

Could someone explain 8 or to me? :S

tag me if u get the answer m not good at this reproduction in plants

 

[Mahoor saqib]

What is Crop rotation?? Can any one explain?

 

[Snowysangel]

tag me if u get the answer m not good at this reproduction in plants

I think you probably describe a vegetative propagation method. Like for layering you use lime tree as an exàmple and explain how a low branch with a node is bent down and a ring of bark about 5 cm wide is removed from it. The ringed portion is completely covered with moist soil while the end of the branch is allowed to hang free. When roots have developed the branch is cut off from the patent plant and allowed to grow on its own. In this way, a number of daughter cheeku trees can be planted from just a single parent plant. Also the same type of child plant is allowed to grow without any changes, which is good for conmwrcial purposes. It's also inexpensive as you don't have to buy anything